By Tuesday morning, the last reminder of two months of puzzlement and frustration on the part of Department of Public Works Director Rich Nota was a gravel-topped 5-foot-square patch in the pavement on the northeast side of the intersection of routes 110 and 111. Beneath it lies a new cap on an abandoned pipe, part of an earlier water system, whose leaking valve was responsible for a loss of 10,000 gallons of water a day over the past two months.
While this is not a “big deal” for a city system, Nota said, it is a lot of water for a small system like Harvard’s.
The problem was discovered in mid-January when the computer monitoring the water level in the tank at the Bolton Road reservoir recorded a sharp decline. Rather than the average daily usage of 19,000 gallons, water was being pumped at the rate of 29,000 gallons per day and Nota had absolutely no idea where all that water was going. Typically, a leak causes water to bubble up somewhere, and in this case it would have appeared in the form of ice on the road. But this leak had never manifested itself.
Nota speculated at first that the leak could be in someone’s basement, perhaps someone who was away for the winter, but there was no way of knowing that unless evidence were visible from the street. While homes on town water are monitored for daily usage, the meters are read only to prepare the quarterly water bills of their owners. Unfortunately, the unusual snow depths prohibited any kind of emergency meter reading.
If the leak was in a stretch along the road, Nota believed there was a strong probability that the water was finding a natural channel to run off—an unused pipe in the system or an old farm drain, from which the water could run downhill into the pond.
When town equipment could not locate the leak, Nota decided to hire outside contractors. Waiting around for the leak to manifest itself could have made it worse, he said. He hired the services of Massachusetts Rural Water Association, a nonprofit group of which Harvard is a member. When its search turned up nothing, Nota engaged the Littleton Water Department, which was also unable to find the source of the leak.
The next step was to hire a specialty company, in this case Prowler Water Conservation Services, whose highly sensitive equipment detects leaks through sound. According to Alan Banks, president of Prowler, Nota first called his company sometime near the second week in February. But, he said, “Snowstorms, cold, frost, high snow piles, and unsafe conditions forced us to prevent starting until [March 3].” Starting then, they spent a week and a half monitoring hydrants (see sidebar).
Search narrows
On March 11 the equipment found the sound it was looking for in the center of town, on the rectangle of land on the southeast side of the intersection. DPW started digging—once they removed the snow—in the soil close to the hydrant. Their “big dig” found nothing, however. The evidence of that failed excavation is a large patch in the pavement across from the General Store.
Prowler’s field engineers fine-tuned their calculations and predicted that the leak was 47 feet north of the first dig, in a far less “convenient” spot: right in the intersection itself. Banks came to Harvard at 3:30 a.m. on Friday, March 13, to verify the determination.
Nota said last Friday that he had a “good feeling” that this was the spot. He commented that people could be picturing a “geyser coming out of the ground,” as might occur in Cambridge. But that wouldn’t be what we would see. A main hadn’t burst; it was a leaking valve, he said.
Early Monday morning, motorists were greeted by a detour around the intersection and a mound of dirt that grew larger throughout the day. By midafternoon the two-month-old mystery had been solved: DPW workers found a leaky valve in a terminal pipe from an older system. When queried, one DPW worker called up from several feet down in the hole that it would be an “easy fix.”
Problem solved
Prowler field engineer Mat Masi was on site during the excavation. He pointed out that the “manifestation,” elusive for two months, had appeared on Monday with the warmer weather, when water bubbled up from the catch basin at the foot of Elm Street.
On Tuesday, Nota said the DPW had capped the old pipe and installed a thrust block against pressure. By the time they were finished backfilling, it was 8 p.m.
Nota confirmed his earlier supposition that the water had been running out an old pipe.
Asked whether he was celebrating, Nota replied that he wasn’t—not quite yet. He is hoping this was the only leak in the system. He won’t know for sure until after a few days of monitoring the water tank level to determine usage.
While this has been a great loss of a natural resource, Nota said the financial loss—the additional cost of pumping the lost gallons—will be absorbed within his budget.
